A passive THz video camera based on lumped element kinetic inductance detectors

TL;DR

This paper presents a passive 350 GHz terahertz video camera utilizing lumped element kinetic inductance detectors, demonstrating near-background-limited sensitivity and real-time imaging capabilities for terrestrial applications.

Contribution

It introduces a terahertz video camera based on LEKIDs, showing their potential for practical terrestrial imaging with high sensitivity and simple fabrication.

Findings

Operates at 2 Hz frame rate with ~0.1 K noise equivalent temperature difference.

Uses a 152-element LEKID array fabricated from 40 nm aluminum.

Achieves background-limited sensitivity close to theoretical limits.

Abstract

We have developed a passive 350 GHz (850 {\mu}m) video-camera to demonstrate lumped element kinetic inductance detectors (LEKIDs) -- designed originally for far-infrared astronomy -- as an option for general purpose terrestrial terahertz imaging applications. The camera currently operates at a quasi-video frame rate of 2 Hz with a noise equivalent temperature difference per frame of $\sim$0.1 K, which is close to the background limit. The 152 element superconducting LEKID array is fabricated from a simple 40 nm aluminum film on a silicon dielectric substrate and is read out through a single microwave feedline with a cryogenic low noise amplifier and room temperature frequency domain multiplexing electronics.